The distance between the two parallel sides in a trapezium is 'd' cm and the parallel sides are 'a' cm and 'b' cm. Area = _____ sq cm
5(a+b)d
0.5(a+b)d
0.3(a+b)d
10(a+b)d
Two parallel sides of a trapezium are of lengths 57 cm and 39 cm. The distance between the parallel sides is 30 cm. Find the area of the trapezium.